Dairy Foods talked to:
Beth Berndt, director of industry solutions for consumer products, CDC Software
Lisa Bezzole, senior marketing manager for food safety & quality solutions, bioMérieux Inc.
Sue Lee, lab manager, rtech laboratories
Ken Micciche, director of marketing, Advanced Instruments Inc.
Fred Weber, president, Weber Scientific
Gary White, market development manager-dairy antibiotics, Neogen Corp.
Food safety is on everyone’s mind: from the farmer to the processor to the consumer, and yes, to the government. Dairy Foods asked six leading suppliers of lab testing equipment and services for insight on how to help dairy processors put safety first, thereby eliminating costly recalls and keeping their reputation intact. Read what the experts say.
Dairy Foods: How has the lab testing environment changed in recent years? What are some of the technological advancements that have taken place in lab testing since the turn-of-the-century?Berndt: Enterprise applications in the food and beverage industry did not even exist some 20 years ago. The applications have always required integral support for food safety related to lab testing, warehousing and production processing activities in order to provide integrated product traceability and rapid recall capability. Our Ross ERP (enterprise resource planning) business solutions has always included detailed production formulations based on both ingredients and finished product quality attributes and customer specifications, as well as the results of lab testing for individual inventory lots. This includes shelflife information, beginning with receipts from ingredient suppliers, through all levels of manufacturing processing, and out to the customer. In the last few years, these same ingredient and product properties, target quality standards and inventory lot lab test results, have also proven necessary in order to provide key input for finished product labeling disclosure of nutritional composition and potential allergen properties. Micciche: The explosion in specialty dairy products means test instruments must be increasingly more versatile and precise. Complex product formulas and raw milk from differing species require analyzers that can consistently and continuously test wide varieties of ingredients. Government proof-of-formula and bacteria count regulations require new levels of instrument accuracy. And cost reduction pressures drive demands for higher lab productivity, less equipment maintenance and accurate measurements. White: Faster, simpler and even more accurate, on-site tests continue to replace off-site traditional laboratory testing methodologies. The industry wants simple, fast tests that anyone with just a little training can accurately perform and interpret. Test kit manufacturers have responded with an increasing number of tests that function with the simplicity of a stick home pregnancy test. Traceability is also now key, requiring test kit makers to develop technology that gives test results permanence, and allows for the easy analysis of large numbers of sample test results. Lee: Initially, wet chemical lab testing was primarily compositional analysis for economic purposes. Butter fat was the component of value and testing was done primarily on fat. Microbiological tests were limited to dye reduction and microscopy, which are not very sensitive and detect only major contamination. More recently, much compositional testing is done by near infrared (NIR) or Fourier transform infrared (FTIR) instrumentation. These instruments have greatly improved analysis efficiency and reproducibility. In many cases, analysis has moved from the lab to the production area. Inline instruments are used in butter and cheese production to control the fat to protein ratio, maximizing fat retention for improved product quality. On the microbiology side, there have been significant advancements in testing methods. Numerous rapid test methods are available, which have the advantage of improved sensitivity in addition to the obvious benefit of speed to results.Weber: Processors are looking for the ability to easily and comprehensively document results for accurate record keeping as well as trend analysis. It can also diminish operator interpretation or error. In demand are instruments and systems with integrated software, or at a minimum printed results. These features are now available in many dairy test categories. For component assay, a major advancement is the LactiCheck milk analyzer. It performs dependable multi-parameter test results for fat, solids-not-fat, protein, density and lactose in just 85 seconds, and provides fast, accurate and economical results for raw or processed milks, whether cow, goat, sheep or buffalo. Data can be printed out, downloaded to a spreadsheet, or both. Based upon established ultrasound technology, the instrument does not require any costly or caustic chemicals to run. It is compact, lightweight, totally portable and reliable. Bezzole: In the area of microbiology, the focus has been on providing methodologies with a high level of accuracy, while providing results as quickly as possible. The increasing adoption of automation has provided a platform for increased standardization, elimination of technical error and the ability to maintain a consistent level of testing. This approach is especially important for sites where there may be a broad range of microbiological expertise. Additionally, as dairy companies develop new products, the introduction of innovative new packaging has led to longer shelflife products and the need for very low-level microbiological testing capabilities.Micciche: Dairy labs are facing stricter government health and safety regulations. Product specifications are tighter as consumers place a higher value on taste, consistency and appearance. Milk producers want clean, bacteria-free milk for long shelflife. And pricing pressures, coupled with the need to meet profit expectations, make cost reduction a never-ending journey. Some of the technologies in use today that were not readily available a century ago include exact measurement of bacteria, water content and components. Berndt: Given the increased regulatory and customer pressures today around food safety, it is important to go beyond providing a historical audit trail of lot quality results based on lab testing in order to help dairy processors comply with these new mandates. A new application offering, CDC Factory, now allows manufacturers to support quality, inventory, production processing and maintenance-related activities by factory personnel in a real-time manner. Access to necessary information in a timely manner helps dairy processors insure that production operators, quality technicians and maintenance staff are empowered, based on key feedback control points, to deliver consistent quality and quantity dairy products every shift of every business day. This includes dispensing specific material handling, production processing and quality sampling tasks and instructions with the right frequency and in sequence. It also enforces the collection of real time information results about quality and processing activities from both people and equipment about every aspect of dairy processing, making this information immediately available at the point of activity for continuous and tangible performance improvements. Real-time performance management helps dairy processors proactively provide higher-quality products at a lower cost, as a result of supporting consistent processes that are repeatable, scalable and transferable from plant to plant, line to line, shift to shift and operator to operator.
Dairy Foods: What types of in-house testing should every dairy be doing these days, as compared to tests they previously sent out?
Micciche: In order to maintain a consistent product, a high-quality milk supply and optimal processing, dairy plants should invest in these four common tests: chemical component analysis, cryoscopy testing, microbiological profiling and pasteurization. All are in transition as they incorporate new technology to meet today’s and tomorrow’s business demands.
Bezzole: Dairy producers have traditionally tested for total aerobic, coliform and Staphylococcus aureus counts. One thing that has changed is the amount of testing that dairy producers do. It is becoming more important for them to trend or track this information as dairy plants have worked to achieve below specification levels of organisms within the product they are striving to improve. They accomplish this objective by creating an internal action level for which they may choose to sanitize or monitor more intensely, always looking for a trend. Since dairy plants can operate all day, this is a lot of data that they must analyze. These types of internal improvement plans are only valuable if they can track and monitor the data more closely. Less traditionally, dairy plants will do specific pathogen testing, and today, some dairies are moving toward an Enterobacteriaceae (EB) count as an additional marker for hygiene. Although the EB count adds another level of control, it should not replace pathogen testing. For now, many dairy plants are collecting EB data and establishing a baseline for which they can monitor their products and strive to continually improve the process.
Weber: Coliform-free water is critical for sanitation, as an ingredient (think of all the bottled water, reconstituted juices and other drinks being bottled within dairies) and for regulatory compliance. For many years most plants had commercial labs do their source water testing. Their in-house test choices were all relatively tedious and time consuming, such as MPN (most probable number) or membrane filtration. Ever since it received PMO (Grade A Pasteurized Milk Ordinance) approval, the Colilert method from IDEXX Laboratories has become an in-house test of choice for certified milk laboratories for negative and positive confirmation for total coliform testing. With less than one minute hands-on time, results are available in 24 hours.
White: In-house testing now available to dairy processors includes safety testing that was never known in the days when all testing was performed off-site. Current testing options include sanitation monitoring, which allows for the almost instant verification of cleanliness of food contact surfaces prior to production; allergen testing kits, which allow HACCP verification of cleaning regimes with simple on-site tests that take only a few minutes; rapid microbial tests, which allow for the early detection of potential spoilage organisms, and allows evaluation and release of ingredients prior to their use in production; and dairy antibiotic tests, which allow for detection of excess antibiotic residues in only minutes.
Dairy Foods: There have always been in-house lab tests that dairies conducted. Please describe how one or more of these have now improved accuracies and/or efficiencies.
White: When compared to the disc assay method for antibiotics used several years ago, the rapid test methods now available on the market provide results in minutes, rather than hours, allowing for screening of the raw milk prior to receipt; and while not specifically quantifying levels of residuals, these test methods provide an assurance that the milk received meets the government standards.
Micciche: Specific to microbiology, after incubation of samples, bacterial colonies are counted visually to determine the microbiological profile. This procedure is called manual visual assessment. But with tedious, visual inspection, lab technicians can process only about one plate per minute-painstaking work that is highly susceptible to error. Now, manual visual assessment can be replaced with automated colony counting technology. With inspection rates of up to four plates in 40 seconds, these high-throughput units slash inspection time by more than 400%. And test results are instantly recorded in the lab’s information system, eliminating the chance for transcription errors and maintaining virtually 100% data integrity.
Weber: A number of dairies are now doing in-house environmental screening for Listeria. Previously they were understandably hesitant to perform pathogen specific work in-house. However, there are two new test methods that are self-contained, a key feature that protects against the chance of contamination in the plant. These AOAC-approved rapid test methods are the SDI-LIB test from Strategic Diagnostics and the InSite test from Hygiena. Presumptive positive results are available for the most common Listeria species in as little as 30 hours at levels as low as one-to-10 CFU (colony forming units) per milliliter.
Bezzole: For microbiological applications, dairy producers typically test for quality indicator organisms, which can serve two main purposes. First, they ensure that their finished products contain only a level of bacteria that falls below their specification ranges. This can also be an indicator of overall production hygiene. Second, they test for specific spoilage indicators. The presence of these kinds of organisms can have a negative financial impact on the dairy manufacturer as high levels of these organisms typically result in the scrap of the product. Historically, dairy (mainly milk producers) have also tested for various microbiological pathogens, but typically, this type of testing is conducted in a central laboratory or reference laboratory outside of the production facility. Over the years, there has been a trend toward simpler, more convenient methods of testing, but always with a concern for cost. There is some tendency to pool samples from different batches or lots and test a larger sample size rather than testing samples from each individual batch. This approach is done to streamline costs. Liquid dairy foods provide a more convenient sample matrix for testing because they are more easily processed for testing.
Berndt: Process enterprise applications are able to look both forward and backward in time, building an inventory audit trail from ingredients and related quality attributes and test results moving in and out of inventory, through production processing and testing, and into inventory as finished product lots with corresponding attributes and lab test results. Every processing activity can be anticipated and scheduled in advance, as well as tracked during ongoing processing and historically over time. This includes managing ingredient purchase orders, inventory receipts and issues, production job reporting, recording lab test results either manually or from a LIM system, and sales to customers. As a result, by leveraging enterprise level information across the factory, the quality lab has time-phased visibility of upcoming activities, active tasks and historical activities, in order to better manage lab testing tasks.
Lee: The use of NIR instruments has greatly improved efficiencies and reduced testing costs. In a minute or less, an analyst can measure the fat, moisture and protein level in a given sample. Traditional wet chemistry methods take hours to obtain the same information. While wet chemical methods are used to calibrate NIR instruments, a production facility need not have the facilities for wet chemical testing. Samples can be collected and sent to an experienced outside lab, such as rtech, for analysis. The wet chemistry results and the instrument readings for each sample are used to construct a calibration curve. Once the calibration is in place, reliable and precise results can be obtained by an operator after minimal training.
Dairy Foods: Please identify some of the new or improved lab tests available to dairy processors.
Berndt: CDC Factory empowers lab personnel, production operators and maintenance personnel to follow best practices and take immediate corrective action to reduce waste and deliver quality products, by adhering to laboratory quality standards, test plans and sampling procedures. But more than being focused just on in-lab testing, it also extends and imbeds quality best practices outside the test lab, by including material handling practices, production equipment operations, equipment maintenance procedures, etc. By empowering all of the people who touch anything that in turn touches dairy products, or relates to any operational process that goes into dairy products, manufacturers can now deliver a consistent level of quality and support continuous improvement within their business processes, based on real-time access to information that supports actionable and corrective decision making.
Micciche: Advanced Instruments’ new alkaline phosphatase test, the Fluorophos ALP Test, assesses pasteurization efficiency in only three-minutes. It is recognized by FDA, AOAC, ISO/IDF and EU, and was adopted as the EU Reference Method on May 6, 2007. It is used on fluid milks, creams and flavored products. In the EU, it has been approved for these same products and cheeses. In addition to rapidly confirming pasteurization, its sensitivity allows processors to quickly find processing issues and correct them before the quality or safety of the product due to improper heat treatment becomes a problem. Advanced Instruments’ subsidiary, Delta Instruments, manufactures, sells and supports affordable, low-maintenance equipment utilized for component analysis. We also have new QCount Colony Counting Technology. This system accurately counts plates, including chromagenic plates, with through put up to 500 plates per hour. Benefits include reduced manual counting, improved accuracy of counts, and ability to store, print and recall images.
Weber: Easygel microbiological media from Micrology Labs uses pectin instead of seaweed-derived agar as a gelling agent in a variety of culture media. It comes as a sterile two-part test unit consisting of a bottle of liquid medium and a petri dish that is pretreated with a special formulation. When the bottle of liquid medium is poured into the pretreated petri dish, calcium ions diffuse from the petri dish pretreatment layer into the liquid causing it to solidify into a semi-solid virtually indistinguishable from an agar-based medium. Complete gelling takes around 40 minutes.
Processors are using the SpotCheck Plus hygiene test as a simple and effective first line of defense in allergen-residue control, rapid-cleaning validation and sanitation monitoring. This all-in-one swab device detects invisible amounts of lactose or glucose residue, a constituent of practically all foods found in a dairy processing plant. You find out in just 60 seconds if any dairy residue is left on a surface, allowing corrective action to be taken on the spot. Simply swab, snap, squeeze and read a definitive color change.
White: Reveal for Total Milk Allergen screens for milk residue at 5ppm in liquid products, clean-in-place rinses and on environmental surfaces. The test is especially useful in allowing multipurpose production lines to be tested quickly and reliably following the sanitation process. The Reveal format for milk allergen testing reduces the time to results from the previous 30 minutes to five minutes, allowing for even better production workflow. After simply dipping a test strip into a sample extract, two lines will form to indicate the presence of at least 5ppm of milk residue (a combined total of casein and whey detected). Soleris is a user-friendly, rapid optical testing system that accurately detects microbial contamination. The system measures microbial growth by monitoring pH and other biochemical reactions that generate a color change as microorganisms grow and metabolize.
Bezzole: bioMérieux has developed and introduced the first automated enumeration system for quality indicator organisms called TEMPO. The process for enumerating quality indicator organisms can be tedious and labor intensive. TEMPO provides an automated platform that provides a more streamlined workflow and eliminates several of the manual steps that are required when using traditional test methods.
In the event of a concern with a possible contamination, locating the source of the contaminant is critical. Each day of uncertainty creates risk for the facility in terms of lost revenue and brand protection. bioMérieux has acquired a new strain-typing technology called DiversiLab, which can complete the genetic typing for an organism in a matter of hours, compared to days with other methods. This level of information can help a facility determine whether or not a contamination is coming from the same strain of organism and provide valuable information in a rapid timeframe to control and manage the source of contamination.
Lee: The DuPont Qualicon BAX System is an automated polymerase chain reaction (PCR) method for the detection of pathogens. It is a highly accurate method for pathogen screening because it is based on amplification and detection of specific DNA fragments. The BAX System provides fast positive or negative screening results. A negative test result can be reported in less than two days.
Advances in the identification and strain tracking capabilities are also offered using the bioMerieux VITEK system and the DuPont Qualicon RiboPrinter.
The VITEK automated biochemical characterization system offers isolate identification to species for most organisms. Identification is obtained based on a series of biochemical reactions that create a biochemical pattern. For uncommon bacteria, our experienced technical staff can use this pattern, along with morphological information from selective agars, ancillary tests and direct microscopic observation to narrow the field to a select few possibilities. For genetic characterization and tracking of strains, we utilize the RiboPrinter microbial characterization system. Using DNA fingerprint analysis, the RiboPrinter can identify environmental isolates, spoilage microorganisms and pathogenic isolates. The bacterial isolate’s genetic pattern is compared to a database containing over 6,400 RiboPrint patterns, representing more than 200 bacterial genera and over 1,400 species and serotypes.